NOTE: As their name suggests hints are not exactly Call of Duty: World at War cheats, and are usually just simple (but very useful) tips on how you can unlock secret level, features, find hidden areas and such. Hopefully these will make playing Call of Duty: World at War even more entertaining.

Online Multiplayer Unlockables
Reach the following ranks on Multiplayer to unlock the desired Multiplayer unlockable.

Online Multiplayer Challenges
Complete the following challenges online to unlock the following:

Aperture Sight for Gewehr 43: Get 75 kills with the Gewehr 43
Aperture Sight for M1A1 Carbine: Get 75 kills with the M1A1 Carbine
Aperture Sight for MP40: Get 75 kills with the MP40
Aperture Sight for PPSh-41: Get 25 kills with the PPSh-41
Aperture Sight for STG-44: Get 75 kills with the STG-44
Aperture Sight for SVT-40: Get 75 kills with the SVT-40
Aperture Sight for Thompson: Get 75 kills with the Thompson
Aperture Sight for Type 100: Get 25 kills with the Type 100
Bayonet for Arisaka: Get 75 kills with the Arisaka
Bayonet for Kar98K: Get 75 kills with the Kar98K
Bayonet for M1 Garand: Get 75 kills with the M1 Garand
Bayonet for M1897 Trench Gun: Get 75 kills with the M1897 Trench Gun
Bayonet for M1A1 Carbine: Get 100 kills with the M1A1 Carbine
Bayonet for Mosin-Nagant: Get 75 kills with the Mosin-Nagant
Bayonet for Springfield: Get 25 kills with the Springfield
Bayonet for Type 99: Get 75 kills with the Type 99
Bipod for BAR: Get 25 kills with the BAR
Bipod for Browning M1919: Get 25 kills with the Browning M1919
Bipod for DP-28: Get 25 kills with the DP-28
Bipod for FG42: Get 25 kills with the FG42
Bipod for MG42: Get 25 kills with the MG42
Bipod for Type 99: Get 25 kills with the Type 99
Box Magazine for M1A1 Carbine: Get 150 kills with the M1A1 Carbine
Dual Magazines for MP40: Get 150 kills with the MP40
Extended Clip for Type 100: Get 25 kills with the Type 100
Flash Hider for M1 Garand: Get 25 kills with the M1 Garand
Flash Hider for M1A1 Carbine: Get 25 kills with the M1A1 Carbine
Flash Hider for STG-44: Get 25 kills with the STG-44
Flash Hider for SVT-40: Get 25 kills with the SVT-40
Grip for Double Barreled Shotgun: Get 25 kills with the Double Barreled Shotgun
Grip for M1897 Trench Gun: Get 25 kills with the M1897 Trench Gun
Rifle Grenade for Arisaka: Get 150 kills with the Arisaka
Rifle Grenade for Gewehr 43: Get 150 kills with the Gewehr 43
Rifle Grenade for Kar98K: Get 150 kills with the Kar98K
Rifle Grenade for M1 Garand: Get 100 kills with the M1 Garand
Rifle Grenade for Mosin-Nagant: Get 150 kills with the Mosin-Nagant
Rifle Grenade for Springfield: Get 75 kills with the Springfield

Round Drum for PPSh-41: Get 75 kills with the PPSh-41
Round Drum for Thompson: Get 150 kills with the Thompson
Sawed-Off Shotgun: Get 75 kills with the Double Barreled Shotgun
Sniper Scope for Arisaka: Get 25 kills with the Arisaka
Sniper Scope for Kar98K: Get 25 kills with the Kar98K
Sniper Scope for M1 Garand: Get 150 kills with the M1 Garand
Sniper Scope for Mosin-Nagant: Get 25 kills with the Mosin-Nagant
Suppressor for Gewehr 43: Get 25 kills with the Gewehr 43
Suppressor for MP40: Get 25 kills with the MP40
Suppressor for Thompson: Get 25 kills with the Thompson
Suppressor for Type 100: Get 25 kills with the Type 100
Telescopic Sight for FG42: Get 75 kills with the FG42
Telescopic Sight for STG-44: Get 100 kills with the STG-44
Telescopic Sight for SVT-40: Get 150 kills with the SVT-40
Telesopic Sight for Gewehr 43: Get 100 kills with the Gewehr 43